There is evidence that certain therapies can cause problems for patients.
Photograph: Alamy

The side effects of antidepressants are well known – nausea, dry mouth, constipation and loss of interest in sex. But what if your depression is being treated by a psychological therapy? Are there any risks in that? Research in the British Journal of Psychiatry suggests there might be – out of 14,587 people who responded to a survey asking about a range of psychological therapies, one in 20 said they had “lasting bad effects” from treatment.

In a separate, in-depth study, researchers found that some people complained of becoming more angry, anxious or losing self-esteem, though they did not follow up to see if these symptoms were resolved. People were more likely to feel harmed if they did not know which psychological therapy they were being given, or if they were not white and heterosexual. So should you worry about being harmed by a dose of psychological therapy?

The solution

Psychological therapies are generally safe. Scott O Lilienfeld, professor of psychology at Emory University in the US and author of a review on the harms of psychological therapies, says it is hard to know if people would have got worse anyway, without therapy. Symptoms such as anger, anxiety and depression can fluctuate over time.

But some psychological therapies do have evidence of harm. Critical incident stress debriefing, often offered after violent events (such as witnessing terrorism), can paradoxically increase the risk of post-traumatic stress disorder.

“Pop psychology says it is best to get everything out of your system, but that may not be everyone’s coping style,” says Lilienfeld. “In crisis debriefing, because it is done in group sessions, you can’t titrate the amount of exposure to the individual, so some may get more upset. The intervention is short, so there may be lack of resolution.”

Recovered memory techniques, meanwhile, have shown a five-fold increase in admissions to mental health institutions and a seven-fold rise in suicidal thoughts. In New Jersey, a programme called Scared Straight that exposed at-risk adolescents to the realities of prison life, actually led to an increase in offending.

Lilienfield thinks it is more important to identify harmful therapists than treatments. Therapists who are confrontational, lack empathy and don’t disclose which treatment they are using should be avoided. There is a list of evidence-based treatments, so you can check the one you are being given works for your condition. Most should work regardless of ethnic group or sexual orientation. Lilienfeld says that if you are no better after a month of therapy, then you should ask your therapist why this is. Some therapies, for example for obsessive-compulsive disorders, should show improvement after a couple of sessions​ (even if it is from feeling terrible to horrible). Your therapist should always ask if your symptoms have got worse. And Lilienfield says you don’t have to feel worse in therapy before you get better.